We include products we think are useful for our readers. If you buy through links on this page, we may earn a small commission. Here’s our process.

The health of your teeth is key to your overall health. Preventing tooth decay or cavities is one of the most important ways to keep your teeth in good condition and to prevent other complications.

According to the Centers for Disease Control and Prevention, close to 30 percent of American adults have untreated dental cavities. Cavities left untreated can destroy your teeth and possibly create more serious issues.

That’s why it helps to know the signs of a tooth cavity and to see your dentist as soon as possible if you think you have one.

When food and bacteria build up in your teeth, it can form plaque. The bacteria in plaque produce acids that have the ability to erode the enamel on the surface of your teeth.

Brushing and flossing your teeth regularly can help get rid of the sticky plaque. If the plaque is allowed to build up, it can continue to eat away at your teeth and create cavities.

A cavity forms a hole in your tooth. If left untreated, a cavity can eventually destroy your tooth. An untreated cavity can also create more serious complications, like a tooth abscess or an infection that gets into your bloodstream, which can be life threatening.

Areas in your mouth that may be at a higher risk of developing plaque include:

  • chewing surfaces of your molars where bits of food can collect in the grooves and crevices
  • between your teeth
  • the bottom of your teeth near your gums

Frequently eating foods that tend to cling to your teeth may also increase your risk of a cavity. Some examples of these foods include:

  • dried fruit
  • ice cream
  • hard candy
  • soda
  • fruit juice
  • chips
  • sugary foods like cake, cookies, and gummy candy

Although cavities are more common among children, adults are still at risk — especially as gums begin to recede away from the teeth, which exposes the roots to plaque.

There are several signs that may indicate the beginning of a cavity. There are also a number of red flags that an existing cavity is getting larger.

Here are some of the most common signs you may have a cavity.

1. Hot and cold sensitivity

Sensitivity that lingers after eating hot or cold food could be a sign that you have a cavity.

When the enamel on your tooth starts to wear away, it can affect the dentin, which is the hard tissue layer below the enamel. Dentin contains lots of microscopic little hollow tubes.

When there isn’t enough enamel to protect the dentin, foods that are hot, cold, sticky, or acidic can stimulate the cells and nerve inside your tooth. This is what creates the sensitivity you feel.

2. Lingering sensitivity to sweets

Although hot and cold are the most common sensitivities when you have a cavity, Dr. Inna Chern, DDS, founder of New York General Dentistry, says a lingering sensitivity to sweets and sugary drinks can also point to tooth decay.

Similar to temperature sensitivity, a lingering discomfort from sweets is often a result of damage to the enamel and, more specifically, the start of a cavity.

3. Toothache

An ongoing ache in one or more of your teeth can indicate a cavity. In fact, pain is one of the most common symptoms of a cavity.

Sometimes this ache can come on suddenly, or it can happen as a result of something you eat. This includes pain and discomfort in or around your mouth. You may also feel pain and pressure when you bite down on food.

4. Staining on tooth

Stains on your tooth may first appear as white spots. As the tooth decay becomes more advanced, the stain can become darker.

Staining caused by a cavity can be brown, black, or white, and typically appears on the surface of the tooth.

5. A hole or pit in your tooth

If the white spot on your tooth (indicating the start of a cavity) worsens, you will end up with a hole or pit in your tooth that you may be able to see when you look in the mirror or feel when you run your tongue over the surface of your teeth.

Some holes, especially those in between your teeth or in crevices, can’t be seen or felt. But you may still feel pain or sensitivity in the area of the cavity.

If you notice a hole or pit in your tooth, make an appointment to see your dentist. This is a clear sign that you have tooth decay.

If you have a concern about a possible cavity, it’s time to make an appointment to see your dentist.

“If you feel temperature or sweet sensitivity that lingers, make an appointment with your dental wellness provider to evaluate the area, especially if the issue lasts more than 24 to 48 hours,” Chern suggests.

A toothache that won’t go away or staining on your teeth are also reasons to see your dentist.

Additionally, seeing the dentist routinely every 6 months and getting X-rays regularly is one of the best ways to prevent cavities or to stop existing cavities from growing into bigger problems, such as root canals and fractures where the tooth can’t be repaired.

Practicing good dental hygiene is the first step in the fight against cavities.

Here are some of the best ways to protect yourself against cavities and more serious tooth decay issues:

  • See your dentist every 6 months for regular cleanings and exams.
  • Brush your teeth at least twice a day with a toothpaste that contains fluoride.
  • Establish a regular flossing routine, cleaning between your teeth at least once a day with floss or a water flosser.
  • Drink water throughout the day to help rinse your teeth and boost saliva flow. Having a dry mouth may increase your risk of cavities.
  • Try not to sip on sugary sodas or juices on a regular basis, and try to cut back on sugary foods.
  • Ask your dentist for preventive products. Chern says if you’re very cavity-prone, ask your dentist for a prescription for high-fluoride Prevident toothpaste or rinse with a fluoride mouthwash like ACT, which is great for kids and adults.

Shop for fluoride toothpaste, floss, water flossers, and ACT mouthwash online.

Cavities start off small, but can cause tooth decay and other serious problems if they’re allowed to get bigger.

If you notice any tooth sensitivity, pain, discomfort, discoloration, or holes in your teeth, don’t hesitate to call your dentist. The sooner you get a cavity checked, the less invasive and more successful the treatment is likely to be.